The present disclosure relates generally to plasma spraying and, more particularly, to equipment for plasma spraying with liquid injection.
Thermal barrier coatings (TBCs) have been widely used to protect the superalloy components in various industries, including components for gas turbine engines. Driven by higher inlet temperature requirements of modern gas turbine engines, high volume production of TBC components has attracted greater attention.
Plasma spray coating process such as Suspension Plasma Spray (SPS) and Solution Precursor Plasma Spray (SPPS) use fine particulates (˜1 micron or less) or liquid solutions to produce the TBC. The TBC adheres to the underlying component primarily by mechanical forces and overspray is generated during the application process. The overspray may have a relatively weak bond with the component such that when additional coating is applied over the overspray, the component may exhibit diminished performance.